Drop-shutter for instantaneous photography



N M d 1.) e o. H. MANN,

DROP SHUTTBR' FOR INSTANTANBOUS PHOTOGRAPHY. 10.267.095

Patented Nov. 7, 1.882.

WITNESSES:

ATTORNEY N. PETERS, Phokrumognpher, wa-hingwn. D. C4

UNrTED STATES PATENT OFFICE.

CHARLES H. MANN, OF PHILADELPHIA, PENNSYLVANIA.

DROP-SHUTTER FOR INSTANTANEOUS PHOTOGRAPHY.

SPECIFICATION forming part of Letters Patent No. 267,095, dated November 7, 1882,

Application filed July 2S, 1882.

To .all whom it may concern Be it known that I, CHARLES H. MANN, a citizen of the United States, residing in the city and county ofPhiladelphia, State of Penn Sylvania, have invented a new and useful Improvementin Drop-Shutters for Instantaneous Photography, which improvement is fully set forth in the following specification and accompanying drawings, in which- Figure l is a view of one face ot' the dropshutter embodying my invention. Fig. 2 is a section thereof' in line a; x, Fig. l. Fig. 3 is a section thereof in line y y, Fig. 1.

Similar letters of reference indicate spending parts in the several tigures.

For instantaneous photography it is important to release the drop-shutter at the desired time in the quickest manner possible. In the operation of devices heretofore in use for such purpose there is delay, which seriously affects the Work to be accomplished, to obviate which is the object of my invention. For this purpose I employ a blast ot' air in such manner that it 4may be directed against the head or piston of the holding-catch of the shutter, and thus promptly release said catch, the air-blast being readily and conveniently under control of the operator.

Referring to the drawings, A represents a drop-shutter for instantaneous photography, which, excepting as far as my invention relates to it, may be otl usual form and construction. The sliding part B of said shutter is notched, as at c a', for the engagement. of a catch, (l, which enters the notch a when the part B is to be held d uring the adjustment of the focus, and enters the notch a when said part is fully set.

D represents acylinderorair-chamber,which is secured to the frame B ot' the shutter, and has within it a sliding head or piston, E, which is connected with the catch O. Communicating with the air-chamberiu front of the piston (No model.)

a', and is guided in plates at opposite ends of the chamber.

Within the chamber D is aspring, H, which bears against the back ot' the piston, for the purpose of returning the catch to its normal position and holding it engaged with the sliding part B of the shutter.

The operation is as follows: Then the shutter is set and everythingin readiness for photographing the object, the operator compresses the bulb yG, thus forcing air into the chamber D and raising the piston E, the action ot which is to withdraw the nose of the catch O from the notch a ofthe part B, whereby the latter under impulse of its springs A is moved and the instantaneous photography ett'ected as usual. The said springs A are connected at one end to the fixed part B of the shutter and at the other end to the movable part B thereof'. Any suitable t'astenings for the springs may be employed, and, as shown in Fig. 1, said springs extend parallel along the outside ofthe shutter.

It will be seen that the operator may control the blast ot' air or compressed air to be directed to the chamber D and hold the bulb while watching the object about to be photographed. The bulb may thus-be quickly operated at the correct time and the catch O instantaneously released, it being noticed that the movement ofthe piston is accomplished in an easy, powerful, and rapid manner, and the catch and part B are quickly disengaged without perceptible loss ot' time and without disturbing or jarring ot' the shutter.

In order to prevent rotation of the catch, I form on the side'of the same a rib, J, which enters a slot in the outer wall of the chamber D, independent of that through which the catch passes, thus serving to guide the catch and always hold it in proper position for its nose to engage with the notch a or a.

The spring at the head ot' the movable part B serves to ease the blowl ot' the same when said part has been released by the catch.

Having thus described my invention, what Iclaim as new, and desire to secure by Letters Patent, is-

l. A photographic drop-shutter provided with a catch, substantially as described, in combination with a chamber and airforcing device or compressor whereby the air directed IOO into said chamber operates said catch, subi catch, iu combination with the rib J, attached stantially as and for the purpose set forth. 1 to said catch and guided to prevent; rotation 1o 2. The photographic drop-shutter provided of the Catch, substantially as and for the pur- With the catch C, in combination with the pose Set forth.

5 chamber D, head or pist-on E, tube F, ziir-foro- C. H. MANN.

ingdevioe or compressor G, and spring H, suh- VitIiesses: stantially as and for the purpose set forth. JOHN A. WIEDERSHEIM,

3. The photographic drop-shutter and its A. l). GRANT. 

